query parameters with default value are marked as optional

[domantas-simplex]

openapi-typescript version

7.8.0

Node.js version

22.14.0

OS + version

macOS 15.4.1

Description

Generating typescript types from parameters with default defined results in a type marked as optional with ?, while it should be generated without marking it as optional.

For example given such parameter:

      parameters:
        - name: status
          in: query
          description: Status values that need to be considered for filter
          explode: true
          schema:
            type: string
            default: available
            enum:
              - available
              - pending
              - sold

We get such type

    parameters: {
      query?: {
        /** @description Status values that need to be considered for filter */
        status?: 'available' | 'pending' | 'sold';
      };
      ...
    };

Notice status? while it should've been status since it will always contain at least the default 'available'.

Including --default-non-nullable flag doesn't fix it.

openapi-typescript/packages/openapi-typescript/src/transform/schema-object.ts

Lines 478 to 484 in d309753

	(hasDefault &&
	options.ctx.defaultNonNullable &&
	!options.path?.includes("parameters") &&
	!options.path?.includes("requestBody") &&
	!options.path?.includes("requestBodies")) // can’t be required, even with defaults
	? undefined
	: QUESTION_TOKEN;

Reproduction

Full YAML example

openapi: 3.0.4
info:
  title: Swagger Petstore - OpenAPI 3.0
  description: |-
    This is a sample Pet Store Server based on the OpenAPI 3.0 specification.  You can find out more about
    Swagger at [https://swagger.io](https://swagger.io). In the third iteration of the pet store, we've switched to the design first approach!
    You can now help us improve the API whether it's by making changes to the definition itself or to the code.
    That way, with time, we can improve the API in general, and expose some of the new features in OAS3.

    Some useful links:
    - [The Pet Store repository](https://github.com/swagger-api/swagger-petstore)
    - [The source API definition for the Pet Store](https://github.com/swagger-api/swagger-petstore/blob/master/src/main/resources/openapi.yaml)
  termsOfService: https://swagger.io/terms/
  contact:
    email: [email protected]
  license:
    name: Apache 2.0
    url: https://www.apache.org/licenses/LICENSE-2.0.html
  version: 1.0.12
servers:
  - url: https://petstore3.swagger.io/api/v3
tags:
  - name: pet
    description: Everything about your Pets
    externalDocs:
      description: Find out more
      url: https://swagger.io
  - name: store
    description: Access to Petstore orders
    externalDocs:
      description: Find out more about our store
      url: https://swagger.io
  - name: user
    description: Operations about user
externalDocs:
  description: Find out more about Swagger
  url: https://swagger.io
paths:
  /pet/findByStatus:
    get:
      tags:
        - pet
      summary: Finds Pets by status.
      description: Multiple status values can be provided with comma separated strings.
      operationId: findPetsByStatus
      parameters:
        - name: status
          in: query
          description: Status values that need to be considered for filter
          explode: true
          schema:
            type: string
            default: available
            enum:
              - available
              - pending
              - sold
      responses:
        '200':
          description: successful operation
          content:
            application/json:
              schema:
                type: array
                items:
                  $ref: '#/components/schemas/Pet'
            application/xml:
              schema:
                type: array
                items:
                  $ref: '#/components/schemas/Pet'
        '400':
          description: Invalid status value
        default:
          description: Unexpected error
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/Error'
      security:
        - petstore_auth:
            - write:pets
            - read:pets
components:
  schemas:
    Category:
      type: object
      properties:
        id:
          type: integer
          format: int64
          example: 1
        name:
          type: string
          example: Dogs
      xml:
        name: category
    Tag:
      type: object
      properties:
        id:
          type: integer
          format: int64
        name:
          type: string
      xml:
        name: tag
    Pet:
      required:
        - name
        - photoUrls
      type: object
      properties:
        id:
          type: integer
          format: int64
          example: 10
        name:
          type: string
          example: doggie
        category:
          $ref: '#/components/schemas/Category'
        photoUrls:
          type: array
          xml:
            wrapped: true
          items:
            type: string
            xml:
              name: photoUrl
        tags:
          type: array
          xml:
            wrapped: true
          items:
            $ref: '#/components/schemas/Tag'
        status:
          type: string
          description: pet status in the store
          enum:
            - available
            - pending
            - sold
      xml:
        name: pet
    Error:
      type: object
      properties:
        code:
          type: string
        message:
          type: string
      required:
        - code
        - message
  securitySchemes:
    petstore_auth:
      type: oauth2
      flows:
        implicit:
          authorizationUrl: https://petstore3.swagger.io/oauth/authorize
          scopes:
            write:pets: modify pets in your account
            read:pets: read your pets
    api_key:
      type: apiKey
      name: api_key
      in: header

Expected result

    parameters: {
      query?: {
        /** @description Status values that need to be considered for filter */
        status: 'available' | 'pending' | 'sold';
      };
      ...
    };

Required

• My OpenAPI schema is valid and passes the Redocly validator (npx @redocly/cli@latest lint)

Extra

• I’m willing to open a PR (see CONTRIBUTING.md)